LT1 with 700R4 questions
Member
Joined: May 2006
Posts: 111
Likes: 0
From: New Jersey
Car: 88 Firebird
Engine: 5.0 ltr
Transmission: 4L60
Axle/Gears: 10bolt 3.23's I think
I have a 93 4l60 trans, they didn't switch to the e version until 94, mine has only a 5 pin plug and I only needed 3 of those for my 88 trans am. I will of course now have other issues because I am going to install a 95 Lt1 in my car with the Lt1 harness and ecm and will need to make the changes to the tailshaft to adapt mine to the computer, I hope I'll only need to make the changes for the vss and an adapter for my speedo ( electronic ) .
Originally Posted by 88blkbird
I have a 93 4l60 trans, they didn't switch to the e version until 94, mine has only a 5 pin plug and I only needed 3 of those for my 88 trans am. I will of course now have other issues because I am going to install a 95 Lt1 in my car with the Lt1 harness and ecm and will need to make the changes to the tailshaft to adapt mine to the computer, I hope I'll only need to make the changes for the vss and an adapter for my speedo ( electronic ) .
Member
Joined: Oct 2005
Posts: 145
Likes: 0
From: South Florida
Car: 90' Trans Am
Engine: 94' LT1
Transmission: Built 700R4
BAH!!!...my speedo still doesnt work and im pulled over all the time lol...
93' LT1 w/ 700R4.....I have a cable hanging out of the PCM that says "SPEEDO 4,000 pulses"...some green wire....not connected to anything and I have no idea where to connect it
Oh yea....i didnt do the engine swap some shop did but never did the speedo
93' LT1 w/ 700R4.....I have a cable hanging out of the PCM that says "SPEEDO 4,000 pulses"...some green wire....not connected to anything and I have no idea where to connect it
Oh yea....i didnt do the engine swap some shop did but never did the speedo
Member
Joined: Oct 2005
Posts: 145
Likes: 0
From: South Florida
Car: 90' Trans Am
Engine: 94' LT1
Transmission: Built 700R4
Originally Posted by Firebat
by cable you mean wire? That speedo 4000pulse output wire hooks up to your speedo.
yea its a small green wire
Supreme Member
Joined: May 2004
Posts: 2,924
Likes: 1
From: Kingston, Tn
Car: 1987 GTA
Engine: LT1
Transmission: T56
Axle/Gears: 9 bolt 3.70 posi
That wire needs to goto a wire under the passenger side of the dash where the bufferbox is located at, it will be either a green or tan wire and that is what goes to the speedo in the car. Now....did they put a 700R4 or 4L60 in the car? From my understanding, the VSS on the 4L60 (not the 4L60E) is different than the one that was in the 700R4 and has to be hooked up to the PCM.
Member
Joined: Oct 2005
Posts: 145
Likes: 0
From: South Florida
Car: 90' Trans Am
Engine: 94' LT1
Transmission: Built 700R4
Originally Posted by Klortho
That wire needs to goto a wire under the passenger side of the dash where the bufferbox is located at, it will be either a green or tan wire and that is what goes to the speedo in the car. Now....did they put a 700R4 or 4L60 in the car? From my understanding, the VSS on the 4L60 (not the 4L60E) is different than the one that was in the 700R4 and has to be hooked up to the PCM.
I put the tranny in....its a rebuilt 90' 700R4
I do have to relocated the PCM because its in the passanger side footwell but like I said......Its a green pulse wire just hanging there...so you say take off the pass side dash? Ive seen the original unhooked computer and some other box there before (vss id assume)....id also assume since my green pulse wire isnt connected then Im geting no lockup from my converter
Now this is a 1994 LT1 though it was converted to speeddensity and is running off of a 1993 LT1 pcm (which I know is meant to work with the 700r4/4l60 w. no electronic control) that why I know!!!!!! this combo should be working, I just need the solution!!!! LOL
Supreme Member
Joined: May 2004
Posts: 2,924
Likes: 1
From: Kingston, Tn
Car: 1987 GTA
Engine: LT1
Transmission: T56
Axle/Gears: 9 bolt 3.70 posi
A big yellow box behind the passenger side of the dash, the VSS buffer box. Big black plug, it will be either a green wire, or a tan wire that goes to the speedo. Hook the dark green wire from the PCM which should be the speedo output wire.
Supreme Member
Joined: May 2004
Posts: 2,924
Likes: 1
From: Kingston, Tn
Car: 1987 GTA
Engine: LT1
Transmission: T56
Axle/Gears: 9 bolt 3.70 posi
the PCM has wires coming straight from the VSS in the tranny, I doublechecked, and the VSS in the '93 has the same part number that the '90 does, the 4L60E has a different part number, so it should work.
I know we talked about this about a year ago, but I became a father, moved from NY to NC, and started a new job since I last worked on this.
From what I am reading, the easiest/best way to keep the LT1/700r4 combo is to push the original reluctor up the output shaft(or remove it) and put a 4l60e pick up in its place...Then the car will run but the speedo won't. Is that the big picture here?
From what I am reading, the easiest/best way to keep the LT1/700r4 combo is to push the original reluctor up the output shaft(or remove it) and put a 4l60e pick up in its place...Then the car will run but the speedo won't. Is that the big picture here?
Can I use this reluctor from Strange Engineering? Looks like it goes on the driveshaft, then I wouldn't have to worry about messing up the output shaft of my tranny...its on the bottom right of the attached page. That pic isn't legible when you bring it up so here is a link to Strange's web catalog. Its on page 129...
Strange Engineering Catalog
Strange Engineering Catalog
Last edited by JDud; Oct 4, 2006 at 08:09 PM. Reason: added info
best way is to remove the speedometer gears off of the 700r4. Then heat up the 4l60e reluctor with a heat gun. Use a huge wrench like 1", 1.5" or use a pipe and pound it on. The reluctor costs maybe $5 from the GM dealership. The 4l60e vss might cost something.
well, i got it all working for about 1000 miles now but the tranny slips. The tranny was rebuilt but by some college kids. I've tried adjusting the tv cable every which way, yesterday, and i think i blew up one of the gears. T56 swap is next.
Overcome it all? Just doing my research here and then picking up a wrench. Without thirdgen.org, I would be very lost. I found all the information for the 700r4 swap with the 94-up LT1 on this site. It might have been scattered all over the place but still on here.
Overcome it all? Just doing my research here and then picking up a wrench. Without thirdgen.org, I would be very lost. I found all the information for the 700r4 swap with the 94-up LT1 on this site. It might have been scattered all over the place but still on here.
Member
Joined: Oct 2005
Posts: 145
Likes: 0
From: South Florida
Car: 90' Trans Am
Engine: 94' LT1
Transmission: Built 700R4
Man, I never got mine working still....Does anyone have a picture of the VSS that I have to plug into....I havent driven the car in quiet some time as I started driving my cadillac at college again....but Im tired of it and missing my TA ALOTT!!!!.... Im almost positive my car is missing the bufferbox or whatever I need to plug into....I need some sort of wiring diagram or something....
if i were you i would give street and performance a call they can fix you right up. they they are VERRRY good with this sort of problem. and they will likley have what parts you need in stock. i bet you need a new tail housing. however call these guys @479-394-5711 they will know. good luck.
Thread
Thread Starter
Forum
Replies
Last Post
Iroc8t8
TPI
53
May 4, 2026 08:09 PM





